Apparatus for fabricating insulating members for lamp bases and the like



1951 A. B. SCHOLES ETAL 2, 73,365 A APPARATUS FOR FABRICATING INSULATING MEMBERS FOR LAMP BASES AND THE LIKE Filed 0ct.- 4, 1947 6 Sheets-Sheet 1' Addison B. S ch0]S OHA/er Mann ATTORNEY INVENTORS 6 Sheets-Sheet 2 06L 1951 A. B. SCHOLES ETAL APPARATUS FOR FABRICATING INSULATING MEMBERS FOR LAMP BASES AND THE LIKE Filed Oct. 4, 1947 v ATTORNEY s A .H wa 4 9 i 4. 4. 3 4

lllllhllnls I v fi /fi /4 m w Addison B- Scholes Oliver Mann Oct. 30, 1951 A. B. SCHOLES ETAL 2,573,365

APPARATUS FOR FABRICATING INSULATING MEMBERS FOR LAMP BASES AND THE LIKE Filed Oct. 4, 1947 6 Sheets-Sheet 3 A B C D H I I I I I 30 30 I I l INVENTORS Addison 5.5021 1% Oliver Mann ATTORNEY A. B. SCHOLES ETAL 6 Sheets-Sheet 4 Oct. 30, 1951 APPARATUS FOR FABRICATING INSULATING MEMBERS FOR LAMP BASES AND THE LIKE Filed Oct. 4, 1947 m n m m P m 9 n u @425 a MN m D .n O m M. A w 7 u 6 5 5 WV W A M A L .N m H E mk fi fi fi P E a? t: a a? 5 u, u 3 5 5 5 A I 5 u. e w w 6 w I a 2 mm 1 My Mm m 6 a. J 5

Oct. 30, 1951 A. B. SCHOLES ETAL APPARATUS FOR FABRICATING INSULATING MEMBERS FOR LAMP BASES AND THE LIKE Filed Oct. 4, 1947 s SheetsSheet 5 ATTORNEY H 5 m W w y 5 e A 5) M 6 Ww M "w w n aJu-a. 2 5 M. 1%

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. A. B. SCHOLES ET AL APPARATUS FOR FABRICATING INSULATING Oct. 30, 1951 MEMBERS FOR LAMP BASES AND THE LIKE 6 Sheets-Sheet 6 Filed Oct. 4"; 1947 JgKGG INVENTOR-S we? Mann Addison B. sd'mles OT ATTORNELY Patented Oct. 30, 1951 APPARATUS FOR FABRICATING INSULAT- ING MEMBERS FOR LAMP BASES AND THE LIKE Addison B. Scholes, Georgetown, and Oliver Mann, Danvers, Mass., assignors to Sylvania Electric Products Inc., Salem, Mass., a corporation of Massachusetts Application October 4, 1947, Serial No. 777,938

4 Claims.

1 This invention relates to electric lamps, especially incandescent lamps, and more particularly to apparatus for fabricating the insulating end member which is a part of the base with which such lamps are provided.

The conventional base for incandescent lamps and similar devices is usually fabricated by disposing a threaded metal shell and a metal eyelet in a pre-determined relative position in a suitable block or jig. Molten glass is then poured into this assembly and, when it has cooled to the desired viscosity, it is molded and pressed into shape by means of a plug or die of desired form. In this method the metal shell is weakened by the annealing resulting from the heat of the molten gob of glass. Another disadvantage is the task of cleaning and pickling the completed base to remove the oxide formed by this heat.

An object of this invention is to provide an apparatus for fabricating buttons of insulating material for electric lamp bases.

Further objects, advantages, and features will be apparent from the following specification when read in conjunction with the accompanying drawings in which:

Figure 1 is a side elevational view of the apparatus of our invention with certain parts thereof shown schematically.

Figure 2 is a perspective view partially broken away, of the glass button which the apparatus of Figure 1 is designed to fabricate.

Figure 3 is an enlarged perspective View partly in section showing the details of the upper and lower molds of the apparatus.

Figure 4 is a fragmentary sectional view of the lower mold.

Figure 5 is a perspective view of a, portion of the apparatus showing the positions which the molds assume at various stations in the fabrication of the glass button.

Figures 6A-6H are fragmentary sectional views of the upper and lower molds showing their relative position at various stages in the button fabricating operation.

The apparatus of our invention embodies the idea of fabricating buttons of insulating material from a. stream or ribbon of molten glass or other moldable insulating material by the action of a pair of molds thereon. The apparatus of our invention is of such a nature that it readily lends itself to adaptation thereof to various types of machines. For example, the apparatus of our invention may be employed on a conveyor type mechanism in which a stream of molten glassis deposited on the conveyor and a plurality of molds disposed in position to act on the stream of glass to form the button. Alter-" natively, a rotatable turret type machine with a plurality of molds mounted in the turret may be employed. The apparatus of our invention is described below with reference to a rotatable turret type machine. However, its application to other types of machines will be readily apparent to those skilled in the art.

In the rotatable turret type machine, a continuous stream of molten glass or other mold-" able insulating material is fed from a suitable tank to the'machine. The machineis provided with an upper and a lower turret which rotate together on a vertical axis. The upper and lower turrets are provided with a, plurality of" upper and lower molds respectively.- The mold ing action is effected by two stationary cams,

one mounted in position to actuate the upper molds and the other mounted in position to ac:

tuate the lower molds. I

In Figure 1 the button moldingmachine |-or our invention is mounted on a table 2. The ma chine l is provided with an upper turret 3 and' a lower turret 4 which are keyed to a shaft 5. The shaft 5 is turned by suitable conventional' by their engagement with a stationary cam l3" mounted on a plate It on the table 2. r

The molten glass from which the buttons are fabricated is fed to the machine from a glass tank l5 which is provided with an orifice'from which a continuous stream of glass 16 flows. This stream of glass, which may be molten cane or tubing, is flattened by rollers I! mounted in brackets I8 as it is drawn from the tank and fed intothe button molding machine. Although cane or tubing may be employed, we have found it preferable to use tubing because it offers the advantage of increased width with decreased glass weight and itdoes not require a complicated and expensive system to effect the fiatten-= ing operation. The ribbon of glass-l6 is directed from the rollers 3 I 1 onto the lower turret ll wherei it is engagediby the molds; 9, and. ll land the Jbuti 1- Actuation of the upper molds '9 is complished by the action of the molds 9 and I thereon. This action, which takes place in sev-" eral steps as the machine rotates,isiillustrated'i in Fig. 5. The detailed constructionofthe upper and lower molds is illustrated in Figures 3 and 4.

In Figure 3, the upper mold 9 is slidably mounte ed in a chamber which is preferably-formed tegral with the upper turret 3; The upper mold:

9 comprises an elongated cylindrical hollow tube 26 and an elongated plunger 27, the lower endof which is designed to form theihnercone'n 'of the button l9, slidably mounted within thetubeg- 26 and seated on a shelf 54 formed integral with thetube 26. A helical spring 28 is threaded over the-upper portion of the tube 26and is seated on the rim 29-01" thechamber 2 5. Ajthreaded cap 38 1s mounted in thetop of the tube 26 and 'isenga'ged by the upper end of the spring 28. Another helical spring 3| is disposed within the hollow tube26 andseated on top of the upper end of the plunger 21. The top of this spring 3| is engaged by that portion of the cap 30 which extends within the tube 26. That portion of the tube 26 which is disposed beneath the turret 3 is of greater diameter than the portion which lies within the chamber 25 and this defines a flange 32 which abuts against the bottom face of the turrat; 3. The lower end of the plunger 21 is provided with a protruding pinor tip 33 which aids in theformation of the aperture 23 in the base 22 of the button. 7 V

In Figure 3, the lower mo1d I0 is slidably mountedin the lower turret 4-. The lower mold I0 comprises an elongated cylindrical tube 34 with 8";CYllI1dIlC2tl head 35of larger diameterthan the tubepn the upper'endthereofand seated on ai shelf 55in-the turret4, and a cylindrical block 36 on the lower end thereof. A helical spring 3'! which encircles-tube 34, is seatedon a rim 38 ofthe-block 36 and is in turn partially enveloped by a chamber 39-which ispreferably; formed integral with the lower turret 4. A threaded bolt 40 with 'a hemispherical head 4 l' is screwed into the-base of the block 36;

A more detailedwiewot the lower mold mechanism is' shown in'Fig-ure 4. The tube 34 is the end of the stop screw 51. This spring 46- supports a pin 41', the head 4810f which is seated on a shoulder 56 in the plunger'45. A helical spring 49 is disposed in the. lower chamber 43. This springis seated-on a set screw 53 which closes "the lower end of the tube 34 and its upper endcengages the head 5D-of thestop screw 5!.

The several operational-steps which efiect the fabrication of the glass button 19 of Figure. 2

from the continuous stream of molten glasswhich I flows from: the glass: tank l5 (Figure- 1)- onto the lower; turret 4 are 5 illustrated in Figure S -and subsequentzfigures. As pointed out above; the ribbon 'ofsmolten glass'-is:fed onto the turret 4 by the rollers ll. The speed of rotation of the rollers I! is adjusted with reference to the speed of rotation of the shaft 5 to which the turrets 3 and 4 are keyed to insure the proper rate of feed of the stream of glass tothe button forming machine.

In Figure 5, the stream of molten glass is fed onto the lower turret 4 from the left. For purposes of clarity, the stream of molten glass has not been illustrated in this figure. As mentioned above, fabrication of the button 19 is effected by the action of the -molds 9 and H] on the stream ofglass. Actuation of the molds 9 and I0 is efiected by-theirengagement with cams II and I3 respectivelydurin a portion of each cycle of rotatiorrof the turrets 3 and 4 in Which molds 9 begin its downward stroke.

and l 0 respectively are mounted.

The o erational steps which effect the fabrication lot the button 19 are described below with reference to Figures 4, 5 and 6A, B, C, D, E, F, G and. The actual moulding of. the. buttonv is accomplished between station. A. and station; D

(Figure 5) Prior .tostation A, i.'1e.,. before either the upper or the lower moldsare actuated by their respective cams, the several parts of. each mold.

are disposed substantially. as shownin Figures 3 and 4.

As vtheupper moldi 9 ."moves into station A, the

cap 30 engages the camJ ({causingthe mold fl'to'i Figures 6A. and 6B illustrate the action which takes place betweenstation .A and station B.v In FigureGA, the .head I. 51 of the plunger?! of theJupper mold..9 hasv started the formation of. the inner cone of the.

; button and-the. pin,33 has. almost, completely pierced the ribbon of glass 16. leaving only. a. thin flash whichsets very quickly. In Figure 6B,"

the upper mold'continuesits downward strokecausing the pin 33'of the uppenmold'to engage the pin 41 of the lower mold, .piercingthe thin flash of glass, and depressing the pin All By de laying the final .formation of the aperture 23I-in the button-until after athin flash ha been formed and has had time to set; a clean aperturefreel from ragged edges is insured. Depression of the pin 41 causes the head v4,8 thereof to recede from its seating engagement with the shoulder 56'and the spring 46' to be compressed. At this points (Fig. 6B) the.head,5'l' of-the plunger 21' of the upper mold .hasseated, itselfon the top of. the plunger 45 of the lower. mold.

FigurefiC illustrates theposition of. the two molds at station B. Atpstation B the upper mold has completed its.fu1l' downward stroke. The

, head 510i the plunger 21. .of, the upper mold which" seated itself on top of the plunger 45.0ffthe lower. mold haspushed the plunger 45 downwardlyjand causes it toseat itself. on the shelf 44 which divides the tubel34f into an upper. chamber 42 anda lower chamber 43. Depressionof the p1unger45f causes thestop screw 51. which. is threaded therein. tomove downwardly. and. compress spring 49. The distance. it between the. periphery of the cylindrical head 35 of the lower. moldnand the peripheryof the headi'l oitheplunger 2fl'ofthe upper mold defines the heightv of l the verticalsection 24-of the button-ML At station B (Figure 5), the hemisphericalv head 4| of thelower moldrhas engagedthe cam. 13-; As themachinerotates-and. the molds move. from stationB-to station -C, the-contour ofthe: cam--l3 is-such that it-causes the lower mold to. begin its upwardrstroker- A s shown inFigure 6D,.

the: upward movementof the -lower; mold. causes 1 the=cylindrical-head 35 oi gtheslowersmold to rise from its seat on shelf 55 in the turret 4. As this upward movement continues it forces the plunger 2] of the upper-mold to moveupwardly and rise from its seat on shelf 54 in tube 26, thus causing the spring 3i (Fig. 3) to contract. At this point the button l9 has been completely formed. Figure 6D shows the position'of the several elements at station C. The full'upward stroke of the lower mold has been completed. The cylindrical head 35 of the lower mold has telescoped within the tube 26 and effected a shearing of the button from the ribbon of glassand formed the vertical section 24 of the button (Fig. 2).

As'the machine rotatesand the molds move from station C toward station D the contour of the cam H is such that it permits .the spring 28, which was compressed in the downward stroke of the upper mold, to expand and draw the tube 26 upwardly. The simultaneous upward movement of the tube 26 effected by the expansion of the spring 28 and the downward force exerted by the expanding spring 3| on the plunger 21 causes the reseating of the plunger 27 on the shelf 54 of the tube 26. In Figure 6E the plunger 27 is shown seated on the shelf 54. This figure also shows the upper mold retracted from the position shown in Figure 6D where the cylindrical head 35 of the lower mold had telescoped within the tube 26 of the upper mold. The button 19 is seated on the cylindrical head 35 of the lower mold and is disposed above and out of contact with the ribbon of glass 16 from which it has been fabricated.

In Figure 6F, as in Figure 6E, the upper mold is continuing its return stroke as the machine rotates from station C to station D. As the upper mold continues its rise, the downward pressure exerted by the head 5'1 on the plunger 45 is relieved and thus permits the spring 49 in the lower chamber 43 of the lower mold It] to expand and push the screw 5! upwardly. Since the screw 5| is threaded in the plunger 45, this causes the plunger 45 to move upwardly and results in the head 50 of the screw 5! reseating itself against the shelf 44. This upward movement of the plunger 45 carries the button H), which is seated thereon, with it, thus moving the lower portion of the button 15 out of contact with the inner face of the cylindrical head 35. This permits the button to cool more quickly.

In Figure 6G the machine has rotated to station D. At station D the return stroke of the upper mold has been completed. The pin 33 of the plunger 21 of the upper mold has withdrawn from its position within the plunger 45 of the lower mold and permitted the spring 46 to push the pin 41 upwardly and cause the head 48 thereof to reseat itself on the shoulder 56 in the plunger 45.

We have found it advantageous to have the lower mold retained for several stations in the same position it is disposed at station D, Figure 6G, to permit the button [9 to cool. After the button has cooled sufi'iciently it may be removed by any suitable means, such as for example a blast of air which blows it into a suitable receptacle. After the button has been removed the lower mold moves out of engagement with its cam l3, dropping the entire mold and effecting a reseating of the cylindrical head 35 on the shelf 55 in turret 4 (Figure 6H). After the button has been removed, the used ribbon of glass from which the button has been fabricated is directed from the turret 4 into a suitable container therefor.

What we claim is:

1. Apparatus for fabricating an article with an aperture therein from a body of moldable insulating material, said apparatus comprising: a male mold comprising a hollow tube internally threaded at one end thereof and having an internal shelf formed therein at the other end thereof, a plunger slidably disposed in said tube and normally seated on said shelf, said plunger having a hole-rforming tip on one end thereof, a spring seated on the other end of said plunger,

and a threaded cap mounted on the threaded end of said tube, the inner end thereof engaging said spring; a female mold in register with said male mold; means for effecting a how of moldable insulating material therebetween; and means for bringing said molds into engagement with one another.

2. Apparatus for fabricating an article with an aperture therein from a body of moldable insulating material, said apparatus comprising: a male mold comprising a hollow tube internally threaded at one end thereof and having an internal shelf formed therein at the other end thereof, a plunger slidably disposed in said tube and normally seated on said shelf, said plunger having a hole-forming tip on one end thereof, a spring seated on the other end of said plunger, and a threaded cap mounted on the threaded end of said tube, the inner end thereof engaging said spring; a female mold in register with said male mold, said female mold comprising a hollow tube having an enlarged cylindrical head on one end thereof and an internal shelf intermediate the ends thereof defining an upper and a lower chamber therein, a plunger slidably disposed in said upper chamber and extending through the cylindrical head on an end of said tube of the female mold, said plunger having an aperture in an end thereof in register with the hole-forming tip on an end of the male mold plunger; means for effecting a flow of moldable insulating material between said molds; and means for bringing said molds into engagement with one another.

3. Apparatus for fabricating an article with an aperture therein from a body of moldable insulating material, said apparatus comprising: a male mold comprising a hollow tube having an internal shelf formed therein at one end thereof and a plunger slidably disposed in said tube and normally seated on said shelf, said plunger having a hole-forming tip on one end thereof; means for imparting a work-forming stroke to said mold; means for effecting the return stroke of the hollow tube of said mold; means for effecting the return stroke of the plunger of said mold; a female mold in register with said male mold, said female mold comprising a hollow tube having an enlarged cylindrical head on one end thereof and an internal shelf intermediate the ends thereof defining an upper and a lower chamber therein, a plunger slidably disposed in said upper chamber and extending through the cylindrical head on an end of said tube of the female mold, said plunger having an aperture in an end thereof in register with the hole-forming tip on the male mold plunger; means for imparting a work-forming stroke to said female mold; means disposed in the lower chamber of the hollow tube of the female mold for effecting the return stroke of the female mold plunger; and means for effecting the return stroke of the hollow tube of the female mold.

4. Apparatus for fabricating an article with an aperture therein from a body of moldable insulatsalesmenal shelfformed the'rem at one end tl-iei'eo'f and a plunger slid'ably disposed in said tube and normally-seated on said shelf, said plunger having -'a hole forming tip onone end thereof a feinale mold in register with said male mold-said female mold comprising a hollow tube having an enlarged cylindrical head on one end thereofand an internal shelf intermediate the ends thereof defining an upper and a -lower chamber therein, a plunger slidably disposed in said upper chamber and extending through the cylindrical head on an end of said tube of the female mold, said plunger having an aperture in'an end thereof in register with the hole-forming tip on an end of the male-moldlplungerg means for efieotinga flow 15 of moldable insulating material between said whe -following 'references are of record m the file'=0f this ipatent:

*UN-ITED sTATEs PATENTS jfiame Date I 3A5A1 Qtterson Nov. 30,1386 Mar. 25, 9: 3 July '8, 1-19 0 1,977,162 Wilcox Oct. 16,1934 FOREIGN PATENTS umbeg. .7 h t 797,345 Fiance Apr. 24, 1936 OTHER; IREFERENCES "Sela" No: 423;1-08, Micklejr (A is; c.) published 

